[1] The jewel was excavated in 1965 on the site of Dunstable Friary in Bedfordshire, and is presumed to have been intended as a livery badge given by an important figure to his supporters; the most likely candidate was probably the future Henry V of England, who was Prince of Wales from 1399.
The jewel is a rare medieval example of the then recently developed and fashionable white opaque enamel used in en ronde bosse to almost totally encase an underlying gold form.
It is invariably compared to the white hart badges worn by King Richard II and by the angels surrounding the Virgin Mary in the painted Wilton Diptych of around the same date, where the chains hang freely down.
[4] A lavish badge like the jewel would only have been worn by the person whose device was represented, members of his family or important supporters, and possibly servants who were in regular very close contact with him.
[9] In 1483 King Richard III ordered 13,000 fustian (cloth) badges with his emblem of a boar for the investiture of his son Edward as Prince of Wales,[10] a huge number given the population at the time.
Other grades of boar badges that have survived are in lead, silver,[11] and gilded copper high relief, the last found at Richard's home of Middleham Castle in Yorkshire, and very likely worn by one of his household when he was Duke of Gloucester.
Though they were surely a symptom rather than a cause of both local baronial bullying and the disputes between the king and his uncles and other lords, Parliament repeatedly tried to curb the use of livery badges.
[19] In the end it took a determined campaign by Henry VII to largely stamp out the use of livery badges by others than the king, and reduce them to things normally worn only by household servants.
Eleanor de Bohun, Mary's sister, had in 1376 also married into the Plantagenet royal family, in the person of King Edward III of England's youngest son, Thomas of Woodstock, 1st Duke of Gloucester (d. 1397), another prominent Lancastrian supporter, and the swan badge was used by his Stafford descendants.
[24] Henry Stafford, 2nd Duke of Buckingham, a descendant of the Beauchamps, Eleanor de Bohun and Thomas of Woodstock, and John of Gaunt, used the swan with crown and chain as his own badge.
Another user of swan insignia around 1400 was John, Duke of Berry, the Valois prince who commissioned two of the most spectacular medieval works featuring white enamel en ronde bosse, the Holy Thorn Reliquary, also in the British Museum, and the Goldenes Rössl.
Dunstable, where the ancient roads of Watling Street and the Icknield Way cross some thirty miles north of London, was frequently visited by the medieval elite.
[33] After its excavation, the jewel was bought by the British Museum in 1966 for £5,000, of which £666 was a grant from the Art Fund (then NACF);[34] other contributions were made by the Pilgrim Trust and the Worshipful Company of Goldsmiths.